Quote Originally Posted by albada View Post
Chemists will be interested in the latest weird problem I had:
Adding the propylene glycol to that developer drops the pH by .07 and raises the temperature by 1 degree C. So it appears to react with something.
Propylene glycol is a weak acid which may lower your pH to some extent. A rise temperature may or may not indicate a chemical reaction in the most narrow sense, think about dissolving sodium thiosulfate in water.
Quote Originally Posted by albada View Post
Adding PG to XTOL does not change its pH, and the only thing my dev has that XTOL lacks is ascorbic acid, so I'm guessing that AA reacts with PG.
XTOL may be much more buffered than your dilute soup. Which brings up an interesting point: Can you see a difference in edge definition between XTOL and your soup?

@Michael: I have no idea why people would recommend sodium ascorbate instead of ascorbic acid, when the latter one is so easy to obtain from any third rate pharmacy.